diff options
author | Kevin Kuehler <kevin@segfault.fun> | 2020-12-11 01:08:26 +0100 |
---|---|---|
committer | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2021-11-30 23:00:21 +0100 |
commit | 0351cbb9e4812fcad694f506800fbadc5182b3f8 (patch) | |
tree | c67b9309d93fdcf1b6429cb6ba4dba27e6733997 /src/resolve | |
parent | resolved: split out function to hash signature (diff) | |
download | systemd-0351cbb9e4812fcad694f506800fbadc5182b3f8.tar.xz systemd-0351cbb9e4812fcad694f506800fbadc5182b3f8.zip |
resolve: Port dnssec verify from gcrypt to openssl^gcrypt
Co-authored-by: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Diffstat (limited to 'src/resolve')
-rw-r--r-- | src/resolve/meson.build | 24 | ||||
-rw-r--r-- | src/resolve/resolved-dns-dnssec.c | 288 | ||||
-rw-r--r-- | src/resolve/test-dnssec.c | 18 |
3 files changed, 259 insertions, 71 deletions
diff --git a/src/resolve/meson.build b/src/resolve/meson.build index c7cb88ac04..d4534cb4a9 100644 --- a/src/resolve/meson.build +++ b/src/resolve/meson.build @@ -176,14 +176,16 @@ tests += [ [['src/resolve/test-resolve-tables.c'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, libm]], [['src/resolve/test-dns-packet.c'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, libm]], @@ -192,28 +194,33 @@ tests += [ 'src/resolve/resolved-etc-hosts.h'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, libm]], [['src/resolve/test-resolved-packet.c'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, libm]], [['src/resolve/test-dnssec.c'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, - libm]], + libm], + [], 'HAVE_OPENSSL_OR_GCRYPT'], [['src/resolve/test-dnssec-complex.c'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, libm], [], '', 'manual'], @@ -223,7 +230,8 @@ fuzzers += [ [['src/resolve/fuzz-dns-packet.c'], [libsystemd_resolve_core, libshared], - [libgcrypt, + [lib_openssl_or_gcrypt, + libgcrypt, libgpg_error, libm]], ] diff --git a/src/resolve/resolved-dns-dnssec.c b/src/resolve/resolved-dns-dnssec.c index 38865bb467..20bb9c7db4 100644 --- a/src/resolve/resolved-dns-dnssec.c +++ b/src/resolve/resolved-dns-dnssec.c @@ -7,6 +7,7 @@ #include "gcrypt-util.h" #include "hexdecoct.h" #include "memory-util.h" +#include "openssl-util.h" #include "resolved-dns-dnssec.h" #include "resolved-dns-packet.h" #include "sort-util.h" @@ -58,7 +59,7 @@ uint16_t dnssec_keytag(DnsResourceRecord *dnskey, bool mask_revoke) { return sum & UINT32_C(0xFFFF); } -#if HAVE_GCRYPT +#if HAVE_OPENSSL_OR_GCRYPT static int rr_compare(DnsResourceRecord * const *a, DnsResourceRecord * const *b) { const DnsResourceRecord *x = *a, *y = *b; @@ -82,12 +83,66 @@ static int rr_compare(DnsResourceRecord * const *a, DnsResourceRecord * const *b } static int dnssec_rsa_verify_raw( - const char *hash_algorithm, + hash_algorithm_t hash_algorithm, const void *signature, size_t signature_size, const void *data, size_t data_size, const void *exponent, size_t exponent_size, const void *modulus, size_t modulus_size) { +#if PREFER_OPENSSL + _cleanup_(RSA_freep) RSA *rpubkey = NULL; + _cleanup_(EVP_PKEY_freep) EVP_PKEY *epubkey = NULL; + _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *ctx = NULL; + _cleanup_(BN_freep) BIGNUM *e = NULL, *m = NULL; + int r; + + assert(hash_algorithm); + + e = BN_bin2bn(exponent, exponent_size, NULL); + if (!e) + return -EIO; + + m = BN_bin2bn(modulus, modulus_size, NULL); + if (!m) + return -EIO; + + rpubkey = RSA_new(); + if (!rpubkey) + return -ENOMEM; + + if (RSA_set0_key(rpubkey, BN_dup(m), BN_dup(e), NULL) <= 0) + return -EIO; + + assert((size_t) RSA_size(rpubkey) == signature_size); + + epubkey = EVP_PKEY_new(); + if (!epubkey) + return -ENOMEM; + + if (EVP_PKEY_assign_RSA(epubkey, RSAPublicKey_dup(rpubkey)) <= 0) + return -EIO; + + ctx = EVP_PKEY_CTX_new(epubkey, NULL); + if (!ctx) + return -ENOMEM; + + if (EVP_PKEY_verify_init(ctx) <= 0) + return -EIO; + + if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) <= 0) + return -EIO; + + if (EVP_PKEY_CTX_set_signature_md(ctx, hash_algorithm) <= 0) + return -EIO; + + r = EVP_PKEY_verify(ctx, signature, signature_size, data, data_size); + if (r < 0) + return log_debug_errno(SYNTHETIC_ERRNO(EIO), + "Signature verification failed: 0x%lx", ERR_get_error()); + + return r; + +#else gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; gcry_mpi_t n = NULL, e = NULL, s = NULL; gcry_error_t ge; @@ -147,10 +202,10 @@ static int dnssec_rsa_verify_raw( ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) r = 0; - else if (ge != 0) { - log_debug("RSA signature check failed: %s", gpg_strerror(ge)); - r = -EIO; - } else + else if (ge != 0) + r = log_debug_errno(SYNTHETIC_ERRNO(EIO), + "RSA signature check failed: %s", gpg_strerror(ge)); + else r = 1; finish: @@ -169,10 +224,11 @@ finish: gcry_sexp_release(data_sexp); return r; +#endif } static int dnssec_rsa_verify( - const char *hash_algorithm, + hash_algorithm_t hash_algorithm, const void *hash, size_t hash_size, DnsResourceRecord *rrsig, DnsResourceRecord *dnskey) { @@ -228,13 +284,77 @@ static int dnssec_rsa_verify( } static int dnssec_ecdsa_verify_raw( - const char *hash_algorithm, - const char *curve, + hash_algorithm_t hash_algorithm, + elliptic_curve_t curve, const void *signature_r, size_t signature_r_size, const void *signature_s, size_t signature_s_size, const void *data, size_t data_size, const void *key, size_t key_size) { +#if PREFER_OPENSSL + _cleanup_(EC_GROUP_freep) EC_GROUP *ec_group = NULL; + _cleanup_(EC_POINT_freep) EC_POINT *p = NULL; + _cleanup_(EC_KEY_freep) EC_KEY *eckey = NULL; + _cleanup_(BN_CTX_freep) BN_CTX *bctx = NULL; + _cleanup_(BN_freep) BIGNUM *r = NULL, *s = NULL; + _cleanup_(ECDSA_SIG_freep) ECDSA_SIG *sig = NULL; + int k; + + assert(hash_algorithm); + + ec_group = EC_GROUP_new_by_curve_name(curve); + if (!ec_group) + return -ENOMEM; + + p = EC_POINT_new(ec_group); + if (!p) + return -ENOMEM; + + bctx = BN_CTX_new(); + if (!bctx) + return -ENOMEM; + + if (EC_POINT_oct2point(ec_group, p, key, key_size, bctx) <= 0) + return -EIO; + + eckey = EC_KEY_new(); + if (!eckey) + return -ENOMEM; + + if (EC_KEY_set_group(eckey, ec_group) <= 0) + return -EIO; + + if (EC_KEY_set_public_key(eckey, p) <= 0) + return log_debug_errno(SYNTHETIC_ERRNO(EIO), + "EC_POINT_bn2point failed: 0x%lx", ERR_get_error()); + + assert(EC_KEY_check_key(eckey) == 1); + + r = BN_bin2bn(signature_r, signature_r_size, NULL); + if (!r) + return -EIO; + + s = BN_bin2bn(signature_s, signature_s_size, NULL); + if (!s) + return -EIO; + + /* TODO: We should eventually use use the EVP API once it supports ECDSA signature verification */ + + sig = ECDSA_SIG_new(); + if (!sig) + return -ENOMEM; + + if (ECDSA_SIG_set0(sig, BN_dup(r), BN_dup(s)) <= 0) + return -EIO; + + k = ECDSA_do_verify(data, data_size, sig, eckey); + if (k < 0) + return log_debug_errno(SYNTHETIC_ERRNO(EIO), + "Signature verification failed: 0x%lx", ERR_get_error()); + + return k; + +#else gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; gcry_mpi_t q = NULL, r = NULL, s = NULL; gcry_error_t ge; @@ -315,16 +435,17 @@ finish: gcry_sexp_release(data_sexp); return k; +#endif } static int dnssec_ecdsa_verify( - const char *hash_algorithm, + hash_algorithm_t hash_algorithm, int algorithm, const void *hash, size_t hash_size, DnsResourceRecord *rrsig, DnsResourceRecord *dnskey) { - const char *curve; + elliptic_curve_t curve; size_t key_size; uint8_t *q; @@ -334,11 +455,11 @@ static int dnssec_ecdsa_verify( assert(dnskey); if (algorithm == DNSSEC_ALGORITHM_ECDSAP256SHA256) { + curve = OPENSSL_OR_GCRYPT(NID_X9_62_prime256v1, "NIST P-256"); /* NIST P-256 */ key_size = 32; - curve = "NIST P-256"; } else if (algorithm == DNSSEC_ALGORITHM_ECDSAP384SHA384) { + curve = OPENSSL_OR_GCRYPT(NID_secp384r1, "NIST P-384"); /* NIST P-384 */ key_size = 48; - curve = "NIST P-384"; } else return -EOPNOTSUPP; @@ -361,25 +482,66 @@ static int dnssec_ecdsa_verify( q, key_size*2+1); } -#if GCRYPT_VERSION_NUMBER >= 0x010600 static int dnssec_eddsa_verify_raw( - const char *curve, - const void *signature_r, size_t signature_r_size, - const void *signature_s, size_t signature_s_size, - const void *data, size_t data_size, - const void *key, size_t key_size) { + elliptic_curve_t curve, + const uint8_t *signature, size_t signature_size, + const uint8_t *data, size_t data_size, + const uint8_t *key, size_t key_size) { + +#if PREFER_OPENSSL + _cleanup_(EVP_PKEY_freep) EVP_PKEY *evkey = NULL; + _cleanup_(EVP_PKEY_CTX_freep) EVP_PKEY_CTX *pctx = NULL; + _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = NULL; + int r; + + assert(curve == NID_ED25519); + assert(signature_size == key_size * 2); + + uint8_t *q = newa(uint8_t, signature_size + 1); + q[0] = 0x04; /* Prepend 0x04 to indicate an uncompressed key */ + memcpy(q+1, signature, signature_size); + + evkey = EVP_PKEY_new_raw_public_key(EVP_PKEY_ED25519, NULL, key, key_size); + if (!evkey) + return log_debug_errno(SYNTHETIC_ERRNO(EIO), + "EVP_PKEY_new_raw_public_key failed: 0x%lx", ERR_get_error()); + pctx = EVP_PKEY_CTX_new(evkey, NULL); + if (!pctx) + return -ENOMEM; + + ctx = EVP_MD_CTX_new(); + if (!ctx) + return -ENOMEM; + + /* This prevents EVP_DigestVerifyInit from managing pctx and complicating our free logic. */ + EVP_MD_CTX_set_pkey_ctx(ctx, pctx); + + /* One might be tempted to use EVP_PKEY_verify_init, but see Ed25519(7ssl). */ + if (EVP_DigestVerifyInit(ctx, &pctx, NULL, NULL, evkey) <= 0) + return -EIO; + + r = EVP_DigestVerify(ctx, signature, signature_size, data, data_size); + if (r < 0) + return log_debug_errno(SYNTHETIC_ERRNO(EIO), + "Signature verification failed: 0x%lx", ERR_get_error()); + + return r; + +#elif GCRYPT_VERSION_NUMBER >= 0x010600 gcry_sexp_t public_key_sexp = NULL, data_sexp = NULL, signature_sexp = NULL; gcry_error_t ge; int k; + assert(signature_size == key_size * 2); + ge = gcry_sexp_build(&signature_sexp, NULL, "(sig-val (eddsa (r %b) (s %b)))", - (int) signature_r_size, - signature_r, - (int) signature_s_size, - signature_s); + (int) key_size, + signature, + (int) key_size, + signature + key_size); if (ge != 0) { k = -EIO; goto finish; @@ -409,10 +571,10 @@ static int dnssec_eddsa_verify_raw( ge = gcry_pk_verify(signature_sexp, data_sexp, public_key_sexp); if (gpg_err_code(ge) == GPG_ERR_BAD_SIGNATURE) k = 0; - else if (ge != 0) { - log_debug("EdDSA signature check failed: %s", gpg_strerror(ge)); - k = -EIO; - } else + else if (ge != 0) + k = log_debug_errno(SYNTHETIC_ERRNO(EIO), + "EdDSA signature check failed: %s", gpg_strerror(ge)); + else k = 1; finish: if (public_key_sexp) @@ -423,6 +585,9 @@ finish: gcry_sexp_release(data_sexp); return k; +#else + return -EOPNOTSUPP; +#endif } static int dnssec_eddsa_verify( @@ -430,11 +595,11 @@ static int dnssec_eddsa_verify( const void *data, size_t data_size, DnsResourceRecord *rrsig, DnsResourceRecord *dnskey) { - const char *curve; + elliptic_curve_t curve; size_t key_size; if (algorithm == DNSSEC_ALGORITHM_ED25519) { - curve = "Ed25519"; + curve = OPENSSL_OR_GCRYPT(NID_ED25519, "Ed25519"); key_size = 32; } else return -EOPNOTSUPP; @@ -447,12 +612,10 @@ static int dnssec_eddsa_verify( return dnssec_eddsa_verify_raw( curve, - rrsig->rrsig.signature, key_size, - (uint8_t*) rrsig->rrsig.signature + key_size, key_size, + rrsig->rrsig.signature, rrsig->rrsig.signature_size, data, data_size, dnskey->dnskey.key, key_size); } -#endif static void md_add_uint8(gcry_md_hd_t md, uint8_t v) { gcry_md_write(md, &v, sizeof(v)); @@ -565,36 +728,32 @@ static int dnssec_rrsig_expired(DnsResourceRecord *rrsig, usec_t realtime) { return realtime < inception || realtime > expiration; } -static int algorithm_to_gcrypt_md(uint8_t algorithm) { +static hash_md_t algorithm_to_implementation_id(uint8_t algorithm) { - /* Translates a DNSSEC signature algorithm into a gcrypt - * digest identifier. + /* Translates a DNSSEC signature algorithm into an openssl/gcrypt digest identifier. * - * Note that we implement all algorithms listed as "Must - * implement" and "Recommended to Implement" in RFC6944. We - * don't implement any algorithms that are listed as - * "Optional" or "Must Not Implement". Specifically, we do not - * implement RSAMD5, DSASHA1, DH, DSA-NSEC3-SHA1, and - * GOST-ECC. */ + * Note that we implement all algorithms listed as "Must implement" and "Recommended to Implement" in + * RFC6944. We don't implement any algorithms that are listed as "Optional" or "Must Not Implement". + * Specifically, we do not implement RSAMD5, DSASHA1, DH, DSA-NSEC3-SHA1, and GOST-ECC. */ switch (algorithm) { case DNSSEC_ALGORITHM_RSASHA1: case DNSSEC_ALGORITHM_RSASHA1_NSEC3_SHA1: - return GCRY_MD_SHA1; + return OPENSSL_OR_GCRYPT(EVP_sha1(), GCRY_MD_SHA1); case DNSSEC_ALGORITHM_RSASHA256: case DNSSEC_ALGORITHM_ECDSAP256SHA256: - return GCRY_MD_SHA256; + return OPENSSL_OR_GCRYPT(EVP_sha256(), GCRY_MD_SHA256); case DNSSEC_ALGORITHM_ECDSAP384SHA384: - return GCRY_MD_SHA384; + return OPENSSL_OR_GCRYPT(EVP_sha384(), GCRY_MD_SHA384); case DNSSEC_ALGORITHM_RSASHA512: - return GCRY_MD_SHA512; + return OPENSSL_OR_GCRYPT(EVP_sha512(), GCRY_MD_SHA512); default: - return -EOPNOTSUPP; + return OPENSSL_OR_GCRYPT(NULL, -EOPNOTSUPP); } } @@ -711,16 +870,22 @@ static int dnssec_rrset_verify_sig( assert(sig_data); assert(sig_size > 0); + hash_md_t md_algorithm; + +#if PREFER_OPENSSL + uint8_t hash[EVP_MAX_MD_SIZE]; + unsigned hash_size; +#else _cleanup_(gcry_md_closep) gcry_md_hd_t md = NULL; void *hash; size_t hash_size; - int md_algorithm; initialize_libgcrypt(false); +#endif switch (rrsig->rrsig.algorithm) { case DNSSEC_ALGORITHM_ED25519: -#if GCRYPT_VERSION_NUMBER >= 0x010600 +#if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600 return dnssec_eddsa_verify( rrsig->rrsig.algorithm, sig_data, sig_size, @@ -731,7 +896,27 @@ static int dnssec_rrset_verify_sig( return -EOPNOTSUPP; default: /* OK, the RRs are now in canonical order. Let's calculate the digest */ - md_algorithm = algorithm_to_gcrypt_md(rrsig->rrsig.algorithm); + md_algorithm = algorithm_to_implementation_id(rrsig->rrsig.algorithm); +#if PREFER_OPENSSL + if (!md_algorithm) + return -EOPNOTSUPP; + + _cleanup_(EVP_MD_CTX_freep) EVP_MD_CTX *ctx = EVP_MD_CTX_new(); + if (!ctx) + return -ENOMEM; + + if (EVP_DigestInit_ex(ctx, md_algorithm, NULL) <= 0) + return -EIO; + + if (EVP_DigestUpdate(ctx, sig_data, sig_size) <= 0) + return -EIO; + + if (EVP_DigestFinal_ex(ctx, hash, &hash_size) <= 0) + return -EIO; + + assert(hash_size > 0); + +#else if (md_algorithm < 0) return md_algorithm; @@ -747,6 +932,7 @@ static int dnssec_rrset_verify_sig( hash = gcry_md_read(md, 0); if (!hash) return -EIO; +#endif } switch (rrsig->rrsig.algorithm) { @@ -756,7 +942,7 @@ static int dnssec_rrset_verify_sig( case DNSSEC_ALGORITHM_RSASHA256: case DNSSEC_ALGORITHM_RSASHA512: return dnssec_rsa_verify( - gcry_md_algo_name(md_algorithm), + OPENSSL_OR_GCRYPT(md_algorithm, gcry_md_algo_name(md_algorithm)), hash, hash_size, rrsig, dnskey); @@ -764,7 +950,7 @@ static int dnssec_rrset_verify_sig( case DNSSEC_ALGORITHM_ECDSAP256SHA256: case DNSSEC_ALGORITHM_ECDSAP384SHA384: return dnssec_ecdsa_verify( - gcry_md_algo_name(md_algorithm), + OPENSSL_OR_GCRYPT(md_algorithm, gcry_md_algo_name(md_algorithm)), rrsig->rrsig.algorithm, hash, hash_size, rrsig, diff --git a/src/resolve/test-dnssec.c b/src/resolve/test-dnssec.c index ed46853eeb..3263095360 100644 --- a/src/resolve/test-dnssec.c +++ b/src/resolve/test-dnssec.c @@ -1,20 +1,19 @@ /* SPDX-License-Identifier: LGPL-2.1-or-later */ #include <arpa/inet.h> -#if HAVE_GCRYPT -#include <gcrypt.h> -#endif #include <netinet/in.h> #include <sys/socket.h> +#if HAVE_GCRYPT +# include <gcrypt.h> +#endif + #include "alloc-util.h" #include "resolved-dns-dnssec.h" #include "resolved-dns-rr.h" #include "string-util.h" #include "hexdecoct.h" -#if HAVE_GCRYPT - static void test_dnssec_verify_dns_key(void) { static const uint8_t ds1_fprint[] = { @@ -174,7 +173,7 @@ static void test_dnssec_verify_rfc8080_ed25519_example1(void) { assert_se(dnssec_verify_rrset(answer, mx->key, rrsig, dnskey, rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0); -#if GCRYPT_VERSION_NUMBER >= 0x010600 +#if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600 assert_se(result == DNSSEC_VALIDATED); #else assert_se(result == DNSSEC_UNSUPPORTED_ALGORITHM); @@ -266,7 +265,7 @@ static void test_dnssec_verify_rfc8080_ed25519_example2(void) { assert_se(dnssec_verify_rrset(answer, mx->key, rrsig, dnskey, rrsig->rrsig.inception * USEC_PER_SEC, &result) >= 0); -#if GCRYPT_VERSION_NUMBER >= 0x010600 +#if PREFER_OPENSSL || GCRYPT_VERSION_NUMBER >= 0x010600 assert_se(result == DNSSEC_VALIDATED); #else assert_se(result == DNSSEC_UNSUPPORTED_ALGORITHM); @@ -788,11 +787,7 @@ static void test_dnssec_nsec3_hash(void) { assert_se(strcasecmp(b, "PJ8S08RR45VIQDAQGE7EN3VHKNROTBMM") == 0); } -#endif - int main(int argc, char *argv[]) { - -#if HAVE_GCRYPT test_dnssec_verify_dns_key(); test_dnssec_verify_rfc8080_ed25519_example1(); test_dnssec_verify_rfc8080_ed25519_example2(); @@ -802,7 +797,6 @@ int main(int argc, char *argv[]) { test_dnssec_verify_rrset2(); test_dnssec_verify_rrset3(); test_dnssec_nsec3_hash(); -#endif return 0; } |